Mass spectroscopy is an analytical technique that involves ionizing molecule samples and sorting the resulting fragments by their mass-to-charge ratio. It works by bombarding vaporized samples with electrons, causing the molecules to ionize or break into fragments. These fragments are then separated based on their mass and detected, allowing researchers to deduce information about molecular structure like molecular weight. It is a sensitive technique that requires only a small amount of sample. While powerful for analysis, it has the limitation of being unsuitable for non-volatile samples that cannot be vaporized.

1. MASS SPECTROSCOPY
MVS RAO

2. According to IUPAC , it is the branch of
science which deals with all the aspects of
mass spectroscopes and results obtained
with these instruments
• it is one of the primary spectroscopic
methods for molecular analysis available to
an organic chemist
• It is a Micro analytical technique, requires
only a few nano moles of the sample to
obtain characteristic information about the
structure and the molecular weight

3. • It is not concerned with non destructive
interaction between molecules and the
electro magnetic radiation
• It involves in production and separation of
the ionized molecules and their ionic
decomposition product and measurement of
the relative abundance of different ions
produced resulting in consumption of the
sample during the analysis(destructive
technique)

4. • It is the most accurate method for
determining the molecular mass of the
compound and its elemental composition
• In this technique molecules are bombarded
with a beam of electrons
• Molecules are ionized and broken into many
fragments, some of which are positive ions

5. • Each kind of ion has a particular mass to
charge ratio(m/e ration), for most of the
ions the charge is one, therefore it is simply
the molecular mass of the ion.

6. BASIC PRINCIPLE

7. • A mass spectrum is the plot of relative
abundance of ions against their
mass/charge ration.
• The basic aspect of organic mass
spectroscopy consist of bombarding the
vapor of organic compound with a beam of
electrons accelerated from a filament to an
energy of 70ev to form positively charged

8. • The additional energy of the electrons is
dissipated in breaking the bonds in the
molecular ion, which undergoes
fragmentation to yield several neutral or
positively charged species.
• This fragmentation may result in an even
electron ion and radical.
• The various positive ions, thus formed can
be accelerated and deflected by magnetic or
electric fields

9. USES

10. • Mass spectra is used in two general ways.
1. To prove the identity of two compounds.
2. To establish the structure of a new
compound.
• It deals with the examination of the
characteristics fragments(ions) arising from
the breakdown of organic molecules.

11. • It helps to establish the structure of a new
compound in several ways
1. It can give the exact molecular mass.
2. It can give a molecular formula or it can
reveal the presence of certain structural
units in a molecule.

12. APPLICATIONS

13. • It has both quantitative and qualitative uses.
• Helps in identification of unknown
compounds.
• Determining the isotopic composition of
elements in a molecule.
• Quantifying the amount of compound in the
sample.
• Determining the structure of a compound by
observing its fragmentation.

14. • Mass spectroscopy is now in very common
use in analytical laboratories that study
physical, chemical or biological properties
of a great variety of compounds.

15. Other uses
• Trace gas analysis, respired gas monitors
• Determining the isotopic compounds of
elements within a sample
• Pharmacokinetics, protein characterization
• Glycan analysis and space exploration.

16. SUMMARY OF MS
• METHOD: Mass spectroscopy
• PRINCIPLE: When a substance in gaseous/vapor state is
bombarded with a beam of electrons the molecules get
ionized or breakdown into fragments. These fragments
are sorted and recorded based on their
masses/molecular weight. The data is then compiled to
deduce the molecular weight of the sample analyzed.
• LIMITATIONS: It is difficult to analyze non-volatile
samples.

17. THANK YOU.